The #researchers then used #NASA’s Chandra X-ray Observatory to confirm that the cold gas in the region was being sculpted by hot #plasma, or electrically charged gas, coming from the galactic center: “If the cold gas were in front of or behind the hot plasma, there wouldn’t be a strong correlation,” Gorski said. “While we did not directly detect the particles moving in the wind, we were able to deduce the direction and energy of the wind.”

There are two main reasons why the discovery of the wind’s presence was more than half a century in the making, ever since Sagittarius A* was first observed in the 1970s, according to Gorski. The first is that instruments have only now become advanced enough to see through the gas and dust that sits between Earth and the center of our galaxy. The other is that Sagittarius A* is in a quiet period, making the wind weaker and therefore much harder to spot. It’s common for supermassive black holes to alternate between active and quiet periods, depending on the supply of material surrounding them.

“Our result essentially says this black hole also has wind, so it’s not weird, and black hole #physics in general work as we expected,” Murchikova said. “But the wind was hard to find because it was so weak. Never before have we seen a weak wind from a black hole.”

Observations from supermassive black holes in other galaxies revealed extremely powerful jets, but those events are rare, Murchikova added. Most of the time, black holes are in a quiet state and just blow a small breeze, which is harder to spot because “no fireworks are coming out.”

The researchers now plan to expand the map of cold gas to a larger region to diagnose the full impact of the wind. The team also wants to make a “movie” of the gas approaching the black hole to observe how the clouds move and be able to estimate how much of the gas the black hole consumes.
A thrilling discovery

Much remains for researchers to discover about how supermassive black holes launch winds, though scientists think that it’s likely due to how the magnetic fields are being spun around the black hole as the gas goes around in its orbit, according to Dan Wilkins, a research assistant professor in the department of astronomy of Ohio State University. Wilkins was not involved with the study.

“Seeing evidence for black hole-driven winds in our own galaxy not only gives us a new avenue for understanding how these winds are driven, but shows that supermassive black holes are still able to launch a wind into their host galaxies even when they are not undergoing active phases of rapid growth,” he wrote in an email.

Jets and winds from black holes are textbook physics, and scientists have observed many supermassive black holes hurling them into space. It’s “thrilling” to have finally caught our own galaxy’s central black hole in the act, said Priyamvada Natarajan, the Joseph S. and Sophia S. Fruton Professor of Astronomy and Physics at Yale University, in an email. Natarajan also did not take part in the study.

“Sagittarius A* has long been the great frustration of galactic center astrophysics: close enough to study in exquisite detail, yet stubbornly quiet, apparently windless,” she said. “This paper dismantles that picture. This is what patient, deep observational astronomy looks like when it pays off.”

There are still many open questions, Natarajan added, but that’s as it should be for a discovery paper. “The authors have handed the community a new observable, and the follow up will be rich,” she said.

Yes, the universe’s expansion is still accelerating, #researchers say. Taking a fresh look at data involving a specific type of stellar explosion, a team of researchers says it has confirmed the long-accepted notion that the universe is expanding at an accelerated rate - the very observation that led to the identification in the 1990s of an enigmatic cosmic force called dark energy.

The study’s results rebut research published last year that concluded that this cosmic expansion is no longer speeding up - a finding that had challenged the basic understanding of the universe.

“The universe is still accelerating,” said astrophysicist Brodie Popovic of the University of Southampton in England, one of the leaders of the study published this month in the journal Monthly Notices of the Royal Astronomical Society.

“There’s still a lot we don’t know and are excited to learn, but we think we’re on the right track,” Popovic said.

The study’s findings, by a team that included two Nobel Prize recipients, were guided by observations in two different datasets of a type of stellar explosion called a Type Ia supernova in order to calculate vast cosmic distances. These supernovas cause the destruction of an object called a white dwarf, the dense remnant of a low- to intermediate-mass star at the end of its lifecycle.

This type of supernova has proven valuable in investigating the universe’s structure based on evidence that all of these explosions have roughly the same luminosity. Their observed brightness differs depending upon their distance from Earth - brighter when closer and fainter when farther - making them useful as cosmic mile markers.

By measuring the brightness of these supernovas as seen from Earth, scientists can gauge the universe’s expansion rate and the variation of that rate over time. Because of the time it takes for light to travel through space, looking at distant objects in the cosmos is like looking back in time.

The Big Bang event roughly 13.8 billion years ago initiated the universe, and it has been expanding ever since. Scientists in 1998 disclosed that this expansion is accelerating, with an invisible force called dark energy as the hypothesized reason.

The universe’s contents include ordinary matter - stars, planets, gas, dust and all the familiar stuff on Earth - as well as dark matter and dark energy. Ordinary matter represents an estimated 5% of the contents. Dark matter, which is known from its gravitational influences on galaxies and stars, makes up an estimated 27%. Dark energy makes up an estimated 68%.

The authors of the 2025 study, which was published in the same journal as the new study, concluded that dark energy is weakening and has stopped accelerating the universe’s expansion.

“Type Ia supernovae are the premier tool for measuring the expansion history of the universe, and provided the first evidence in 1998 that cosmic expansion is accelerating due to dark energy,” said astrophysicist Adam Riess of Johns Hopkins University in Maryland, a co-author of the new study and a Nobel laureate in physics in 2011 for the co-discovery of the accelerating expansion of the universe.

“Over the past decade, a group at Yonsei University has argued that supernova distances should be calibrated differently by accounting for the ages of the stars that eventually explode, and that this ‘age effect’ could substantially alter the evidence for acceleration. In our study, we found no evidence for the claimed ‘age effect’ in the largest calibrated supernova samples used by the cosmology community over the last decade,” Riess said.

Astrophysicist Young-Wook Lee of Yonsei University, located in Seoul, was one of the leaders of the 2025 study. Lee defended the findings of his team, and said the main arguments made by the researchers in the new study have “serious methodological flaws or lead to conclusions that are internally inconsistent by their own logic.”

The researchers in the new study expressed confidence in their methodology and their conclusions confirming acceleration.

The physical nature of dark energy remains unknown. Platforms such as the newly operational Vera Rubin Observatory in Chile and the forthcoming Nancy Grace Roman Space Telescope, due to be launched in August, may provide some insight.

“We’re hoping the new data we get from Vera Rubin and the Nancy Grace Roman Space Telescope will help us narrow down what dark energy really is,” Popovic said.

(Reporting by Will Dunham; Editing by Daniel Wallis)

Sustained maneuver has a propulsion problem. As missions grow more mobile, contested and long-lived, propulsion should be judged across the full mission, not at launch.

For years, space architecture was treated mostly as a question of placement: where to put a spacecraft, and how reliably it could hold position. That framing is now too narrow. A growing number of missions need to reposition, retask, inspect, avoid threats, persist, support logistics or simply preserve options as the operating environment changes. The community is taking maneuver more seriously — and that shift is overdue.

House appropriators back $55.5 billion Space Force budget, omit reconciliation funds.
Draft defense bill funds Pentagon at requested discretionary levels but excludes $350 billion in proposed reconciliation spending, casting doubt on Golden Dome and other space programs

#WASHINGTON — #Satellite data provider Spire Global has partnered with one of Germany’s largest defense contractors to pursue space-based missile warning and hypersonic threat detection capabilities.

The companies announced a memorandum of understanding June 10 under which Spire and Diehl Defence will explore collaboration on satellite-based intelligence and early warning systems designed to detect ballistic and hypersonic missile threats.

The agreement does not include a contract award or financial terms, but it positions the companies to pursue future opportunities in Europe’s expanding space-security and missile-defense market.

Spire, which operates a constellation of small satellites in low Earth orbit, collects and analyzes radio-frequency signals, weather data, aircraft and maritime tracking information, and other forms of geospatial intelligence.

Spire’s chief executive Theresa Condor said the collaboration combines the company’s satellite and data capabilities with Diehl’s defense expertise to help strengthen security from space for Germany and Europe.

Diehl’s chief executive Helmut Rauch said the goal is to connect intelligence gathered from space-based systems with weapons platforms and military command-and-control networks.

The partnership comes as Europe accelerates efforts to develop sovereign missile-warning capabilities following Russia’s invasion of Ukraine and amid growing concerns over ballistic and hypersonic missile threats.

The United States operates extensive missile-warning satellite networks through programs managed by the U.S. Space Force. European nations have historically relied more heavily on U.S. capabilities but are now examining independent space-based sensing architectures as governments seek greater strategic autonomy in defense and intelligence.

Germany has emerged as a key participant in those discussions, creating potential opportunities for companies able to provide satellite-based surveillance and early warning services.

Detecting hypersonic missiles remains one of the most challenging missions for modern militaries. Unlike traditional ballistic missiles, hypersonic weapons can maneuver during flight while traveling at speeds exceeding five times the speed of sound, making them more difficult to track and intercept.

The agreement builds on Spire’s investment in Germany. The company recently announced an expansion of its satellite manufacturing facility in Munich intended to support sovereign satellite missions.

#Amazon was relieved of a government deadline to have half of its planned satellite constellation up and running by next month, delaying the risk that regulators might suddenly curb the operation

#NASA astronauts returned to the International Space Station (ISS) after their preventive evacuation to the docked Dragon spacecraft over an air leak on the #ISS Russian segment, Roscosmos Deputy Head for Piloted Programs Sergey Krikalyov said.

"According to our information, the NASA astronauts have returned to the ISS to continue work in normal mode. Nothing endangers the crew’s safety. Earlier, the NASA crew was transferred to the docked Crew Dragon spacecraft for the time of repairs in a transfer chamber," the Roscosmos official said.

NASA Spokesperson Bethany Stevens said earlier on June 5 that NASA had ordered astronauts aboard the International Space Station to transfer to their docked Dragon spacecraft as a measure of precaution as the Russian crew was carrying out repairs on the Zvezda module after detecting new air leaks,

#Roscosmos announced on June 5 that cosmonauts had found two potential air leaks in the Zvezda module. The first leak was quickly sealed and work was underway to seal the other, it said.

#SpaceX denied fast index entry by S&P 500. S&P Global said on Thursday it was not changing the requirements for entry into its major indices, dealing a setback to Elon Musk’s SpaceX by effectively ruling out a swift entry for the world’s biggest-ever IPO into the benchmark S&P 500 index.

Musk has rewritten the IPO playbook for ⁠SpaceX in many ways from planning to give retail investors a bigger role in allocations to pushing for early index inclusion, and structuring governance to preserve strong founder ​control.

The company is raising US$75 billion and targeting a $1.75-trillion valuation that would place it among the top 10 most valuable U.S.-listed firms, even as only a fraction of its shares are available for trading.

But S&P said “exceptions to the financial viability, seasoning, and IWF (investable weight factor) requirements should not be granted solely based on market capitalization.”

To be included in the S&P 500, a company must be profitable under Generally Accepted Accounting Principles in its most recent quarter as well as for the sum of its most recent four quarters, according to one of the rules S&P left unchanged.

SpaceX posted a net loss of $4.94 billion in 2025, even as revenue rose 33 per cent to $18.67 billion.

Investor consultations

S&P had consulted with investors about shortening the time a megacap company must be publicly listed before joining its indexes, waiving minimum float requirements and removing its profitability requirement.

The S&P 500 is Wall Street’s most widely followed benchmark. Passive S&P 500 index funds with trillions of dollars in assets would have been forced to buy up SpaceX shares had rules been changed to admit it to the index.

“It speaks highly of the credibility of S&P Dow Jones Indices to be rules-based and make sure there’s profitability before entrance to the index,” said Art Hogan, chief market strategist at B. Riley Wealth.

“Making exceptions because companies are so large and have been private so long yet are still not profitable, didn’t make a great deal of sense.”

Nasdaq has already made changes that will make it easier for SpaceX, Anthropic and other newly listed megacaps to join its Nasdaq 100 index.

Nasdaq 100 index funds will be forced to buy a sizeable portion of publicly available SpaceX shares when the company joins that index.

Exchange operators have ramped up efforts to boost initial public listings as richly valued technology firms such as SpaceX and AI giants Anthropic and OpenAI edge closer to public offerings, amid growing concerns over a steady decline in the number of U.S.-listed companies.

S&P Global said it would modify entry rules for its broader S&P Total Market Index and Dow Jones U.S. Total Stock Market Index, creating a pathway for SpaceX to join those less widely followed indexes.

SpaceX has also already become eligible for inclusion in both the Russell U.S. Equity Indexes and the FTSE Global Equity Index Series under the newly announced fast-entry rules from the index provider FTSE Russell.

Noel Randewich, Pritam Biswas and Shivansh Tiwary, Reuters

#NASA declares its Mars Maven spacecraft dead after six months of silence. The space agency confirmed Wednesday that the mission had ended after more than a decade of observations.

Launched in 2013 to study the red planet’s atmosphere from orbit, Maven mysteriously fell silent in early December after passing behind Mars. Data indicated the spacecraft went into a fast spin, which disrupted its orbit and drained the onboard batteries.

A review board convened by NASA earlier this year concluded that the spacecraft is useless and unable to be recovered. An investigation continues into what caused the problem.

Besides studying Martian weather and observing a stray interstellar comet last year, Maven helped relay information from NASA’s Curiosity and Perseverance rovers on the surface.

Maven’s lead scientist, Shannon Curry of the University of Colorado Boulder, said the spacecraft made a number of “amazing discoveries.”

Maven “has truly advanced our understanding of the Martian atmosphere and evolution,” she said in a statement.

Marcia Dunn, The Associated Press

#China's #Shenzhou-21 astronaut crew returns to Earth